Old and New Arithmetic - Ivars Peterson (MathLand)
"Three merchants have invested their money in a partnership..." This problem appears in a mathematics textbook known as the Treviso Arithmetic. The original book, written in a Venetian dialect, had no formal title, and its author is unknown. Treviso is
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Oliver Knill
Research, teaching, and media by this preceptor in Harvard's math department. Knill began in dynamical systems, tackling first ergodic and spectral theoretical questions, then probability theory and elementary number theory. This led to his "passion for
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Online Math Help for All - Ramachandran Seerangan
Primers and problems, a math dictionary, worksheets organized by grade and concept, and more. See in particular Seerangan's YouTube channel, where he posts narrated whiteboard videos of step-by-step solutions to specific problems.
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Online Math Tests Home Page - Elias Saab
This site has problems that help sutudents get ready for College Alegbra or Calculus. It also has problems in Geometry and Trigonometry. All the problems have complete solutions that are given when one hits the submit button. Tests covered include: MPE-4-10,
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On the 3x + 1 Problem - Eric Roosendaal
Numerical data and some conjectures on this problem, also known as the Collatz problem or the Syracuse problem. All numbers up to 29,300 * 10^12 (~ 26 * 2^50) have been checked for convergence.
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On This Day in Math - Pat Ballew
Mathematically significant events, births, deaths, and more, posted every calendar day. Ballew's blog reveals his thoughts on teaching math. His links and explanations written using The Geometer's Sketchpad include triangle medians; angle bisectors in
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OOG: the Object Orientation Game - MCM Productions
MCM Productions' first publicly released software application. This 4-in-1 tiling puzzle game for the MS-Windows environment allows players to test their problem solving ability with over 300 puzzles, including Tangrams, Pentominoes, Hexagons and Polyominoes.
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Open Middle - Johnson, Nanette; and Kaplinsky, Robert
"Open middle" problems, hints, and answers, all aligned to the Common Core State Standards (CCSS). Introduced by Dan Meyer, these kinds of math challenges have a "closed beginning," meaning that they all start with the same initial problem; a "closed
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Open Problem Garden - Matt DeVos and Robert Šámal
A collection of unsolved problems -- mainly, graph theory, combinatorics, and number theory. A wiki for each open problem includes relevant bibliographical citations, importance rating, and recommendation for undergraduates. Navigate by math subject,
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Operations Research - J. E. Beasley
OR-Notes are a series of introductory notes on topics that fall under the broad heading of the field of operations research (OR). Beasley includes practice questions ("tutorials"), links to other web resources, and past exams.
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